FMUTIL

Fortran Miscellaneous UTILities

Author

Bharat Mahajan (https://www.researchgate.net/profile/Bharat_Mahajan2)

Introduction

FMUTIL is a modern object-oriented Fortran library that provides (as of now):

Data structures
- Vector (similar to C++ STL Vectors) with fast vector slicing
- List (similar to Python List)
Root-finding algorithms
- Polynomial roots by computing eigenvalues of the companion matirx (require Intel MKL)
- Roots of a nonlinear equation using Brent's algorithm
A simple binary search method for sorted arrays

Repository

https://github.com/princemahajan/FMUTIL

How to Use

For Vector data structure of any type, define the type of the Vector element and the assignment operation as follows.

    module TestModule
    use FMUtil
    type, extends(VecElem) :: relem
        real :: rdata
    contains
        procedure :: AssignVecElem => assign_relem
    end type relem

    contains

    subroutine assign_relem(lhs, rhs)
        implicit none
        class(relem), intent(out) :: lhs
        class(VecElem), intent(in) :: rhs
        select type (rhs)
        class is (relem)
            lhs%rdata = rhs%rdata
        end select    
    end subroutine assign_relem
    end module TestModule

Then, use Vector using

    program Test
    use FMUtil
    use TestModule

    integer :: ctr
    type(Vector) :: vec
    type(relem) :: rd1, rd2

    rd1%rdata = 3.1416
    ctr = vec%PushBack(rd1)    
    rd1%rdata = 2.718
    call vec%Insert(2,[rd1, rd1])

    do ctr = 1, vec%Size()
        rd2 = vec%ElemAt(ctr)
        print *, 'int(', ctr, ')=', rd2%rdata        
    end do    
    end program Test

List can be used as

    program Test
    use FMUtil

    integer :: ctr
    type(List) :: list
    class(*), allocatable :: item
    type(relem) :: rd1
    rd1%rdata = 3.1416

    ctr = list%PushBack(100)
    ctr = list%PushBack(rd1)
    ctr = list%PushBack(rd1%rdata)
    ctr = list%Insert(3,'pi')    

    do ctr = 1, list%Size()
        item = list%Item(ctr)
        select type (item)
        type is (real)
            print *, item
        type is (relem)
            print *, item
        type is (integer)
            print *, item
        type is (chanracter(len=*))
            print *, item
        end select
    end do  
    end program Test

See the test program files, test.f90 and testmod.f90, in tests folder for more features and functionality.

Installation

FMUTIL is tested with Intel Fortran Compiler and MinGW-W64 gfortran (8.1.0) on Windows platofrm only. Doxyfile is provided for generating extensive API documentation using Doxygen. FMUTIL has only dependency on Intel MKL for polynomial root-finding. The CMakeLists file is provided along with additional CMake modules for compiler options and a Find module for finding and linking Intel MKL is also provided. These files can be used to auto generate Visual Studio projects or makefiles on Windows and Linux using CMake. A find module for FMUTIL is provided that generates CMake config files for easily linking FMUTIL using the find_package() command. The steps to link FMUTIL in cmake-based projects are:

Set the environment variable "MKLROOT" with the path to the Intel MKL installation directory. On typical Windows system, it looks something like "C:\Program Files (x86)\IntelSWTools\compilers_and_libraries_2019.0.117\windows\mkl"
Set the environment variable "IFORT_COMPILER20" with the path to the Fortran Compiler installation directory. On typical Windows system, it looks something like "C:\Program Files (x86)\IntelSWTools\compilers_and_libraries_2020\windows"
In cmake GUI or command-line, set FMUTIL_INSTALL_LIB_DIR to the desired directory, where the compiled library, modules, and cmake config files will be installed.
In cmake GUI or command-line, set FMUTIL_INSTALL_BIN_DIR to the desired directory, where the compiled test executables will be installed.

In your project CMakeLists.txt, insert

    find_package(FMUTIL REQUIRED 0.1 CONFIG PATHS "<SAME_PATH_AS_IN_FMUTIL_INSTALL_LIB_DIR>" NO_CMAKE_PACKAGE_REGISTRY)
    target_link_libraries(<YOUR_TARGET_NAME> FMUTIL::FMUTIL)